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10 votes
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SFP+ transceiver's ability to do 1GbE

Short answer: in theory yes, in practice no. Long answer: There are SFP+ optics which can also work at 1 GbE, I've talked (sorry, no other source than that) to people who were experimenting with it ...
Lysis's user avatar
  • 196
7 votes
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Can a pair of matching WDM transceivers be connected directly?

Mutiplexers arrange multiple wavelengths onto a shared fiber - they don't change the signals. So yes, if the transmitter/receiver wavelengths match you can connect two transceivers with standard patch ...
Zac67's user avatar
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5 votes
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10G SFP+ transceiver with OM4 fiber cable - Maximum cable length?

If you have not already bought and installed the cable then you should install single mode fiber instead and use LR transcievers. This is the officially supported way to do links of that distance at ...
Peter Green's user avatar
  • 13.3k
5 votes

SFP-10G-LRM compatible with Single Mode Fiber?

It can use multimode, but it doesn't have to: The Cisco 10GBASE-LRM Module also supports link lengths of 300m on standard Single-Mode Fiber (SMF, G.652). From the data sheet.
Ron Trunk's user avatar
  • 67.7k
5 votes
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What certifications are there for Fiber Optic termination and splicing?

It's not terribly difficult to train yourself, if you care about the doing. If you care about selling yourself more, BICSI will happily take your money as a certifier. Probably better if you can get ...
Ecnerwal's user avatar
  • 2,746
4 votes

detect SFP transmit wavelength

Relying on SFP MSA is not a good options, as these specs are often faked to allow a specific switch to work with an incompatible device (I've see lots of bidirectionnal SFP which are identified as ...
Golgot's user avatar
  • 427
4 votes
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Optical fibers out of service

does a bad equipment or a too high signal could break an optical fiber silica Not likely. To actually damage the fiber, you'd need very high transmit power (several Watt) not common with off-the-...
Zac67's user avatar
  • 84.9k
4 votes

What is the difference between LR1 and LR4 optics?

As in 10GBASE-LR versus 40GBASE-LR4? -L stands for long ~1300 nm wavelength (as opposed to -S for 850 nm and -E for ~1550 nm). -R stands for large block code 64b/66b. The suffix 4 stands for the ...
Zac67's user avatar
  • 84.9k
3 votes

Macsec and Optics

Assuming you're talking about fiber optic transceivers commonly used in network equipment, the answer is MACsec has no impact on them. MACsec is a layer 2 protocol, while transceivers are simply ...
Ron Trunk's user avatar
  • 67.7k
3 votes
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Power at the terminals of a PLC fiber optic splitter

Here is an answer I found at the web site of a fiber optics manufacturer A common question we receive is whether a 50/50 beamsplitter can be used in reverse, to combine the signals ...
user7641's user avatar
3 votes
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Why do higher speed links require a stronger signal?

You can visualize a high-speed pulse signal by using an eye pattern. The "eye" opening is the measure of distinction between levels (vertical) and pulse sequence (horizontal). The larger the ...
Zac67's user avatar
  • 84.9k
3 votes
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SFP+ 10GBASE-LR and attenuator

Most 10 km PHYs can talk to each other even over very short links. The key is whether the max launch power overshoots the max receive power, effectively blinding the receiver. With this transceiver, ...
Zac67's user avatar
  • 84.9k
2 votes

detect SFP transmit wavelength

Anything that conforms to the SFP MSA ("specs") has an I2C interface to a PROM with those values stored within it. I have yet to see an SFP (or SFP+) that did not have that interface.
Ricky's user avatar
  • 32.3k
2 votes

What certifications are there for Fiber Optic termination and splicing?

The standards body, which also provides training and certifications, is BICSI. You must join BICSI. There are then classes, some offered by BICSI, some offered by approved third parties. You take ...
Ron Maupin's user avatar
  • 99.8k
2 votes
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Latency of AOC vs passive DAC

The difference here is incredibly trivial - literally on the order of single-digit nanoseconds. The amount of time it takes to get the packet organized and across the switch is likely 2- to 3- orders ...
rnxrx's user avatar
  • 6,114
2 votes

Do low temperatures cause problems installing new optical wiring or fixing broken optical cables by splicing?

In addition to the excellent answer by user36472: I know that some of our contractors refuse to do ground works when temperatures are below 0 degrees celsius, since digging up fibers in frozen ground ...
Teun Vink's user avatar
  • 17.4k
2 votes
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What is the purpose of defect limit in Zone D in criteria for MM‐PC Connectors (IEC 61300‐3‐35)

Not all defects are negative. Any protruding defect, or loose contaminant particle, can prevent contact (holding the connector faces apart), scratch the mating connector, or in the case of a loose ...
Ecnerwal's user avatar
  • 2,746
2 votes
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Using XFP-10G (120 KM Range) on Juniper MX routers

When we run the command 'show chassis hardware' , there is no such mentioning that its a NON-JNPR XFP. Based on this , can we say confidently that it must be XFP from Juniper side? The thing you're ...
Jordan Head's user avatar
  • 7,109
2 votes

SFP+ 10GBASE-LR and attenuator

Launch power max 0.5 dBm, receive power max 0.5 dBm. Should be fine. Also, -8.2 to 0.5 dBm is a huge range for launch power, although this may be specified with aging in mind (launch power reduces ...
alex.forencich's user avatar
2 votes
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Is there a difference between BIDI LR and DFB BiD or are they compatible?

25GBASE-BR is standardized in IEEE 802.3cp-2021. There are quite a few pre-standard transceivers out there (BiDi, BX, ...) but pretty much all of them use the same 1270/1330 nm wavelength pair that ...
Zac67's user avatar
  • 84.9k
2 votes
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Single-Mode Fiber Optics

You can verify your assumption by looking at the offers at the vendor of your choosing. Traditionally, SMF optics used to be a lot more expensive than MMF ones due to the laser/detector technologies ...
Zac67's user avatar
  • 84.9k
2 votes

How can GMPLS unify signalization plain of all telecommunications network technologies?

The idea of GMPLS is that it's hardware and media agnostic. Optical networks are just one kind of media that GMPLS can be used on.
Ron Trunk's user avatar
  • 67.7k
2 votes
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Can wrong SFP module damage equipment?

No, not normally. By design, all SFP/SFP+/SFP28/... modules are electrically compatible. The maximum power-supply current defined by the SFF standards is 500 mA. All signal contacts are well defined ...
Zac67's user avatar
  • 84.9k
1 vote
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Is there a way to know the length of the cable used between the connected SFPs on a switching/routing device?

No, you can find out with optical test equipment such as an OTDR, but not with the less-sophisticated telemetry available in a router/switch. You can know the path loss (limited by the accuracy of the ...
Jeff Wheeler's user avatar
  • 5,478
1 vote
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How does "bits per second" relate to wavelength?

such as 1GbE can be joined up together so that they share the same 10G wavelength That is trying to say that you can combine multiple 1G links (at the data link layer) to a single 10G link so you'll ...
Zac67's user avatar
  • 84.9k
1 vote

SFP-10G-LRM compatible with Single Mode Fiber?

If you use the Cisco utility to search for transceiver compatibility on a router/switch model with SFP+ ports, it WILL list the -LRM part twice. XcverProdID Reach Media SFP-10G-LRM 220m MMF SFP-...
paulfixit's user avatar
1 vote

Optical fibers out of service

Hopefully I'm understanding the question correctly. If you're asking if bad optics, or an optic shooting light thats too hot (high transmit dbm) can damage the core in the fiber cable itself; then no. ...
DragonFist616's user avatar
1 vote

Do low temperatures cause problems installing new optical wiring or fixing broken optical cables by splicing?

In Finland we do installs also in winter. If the ground is frozen, it can be hard to dig, but also other cables may be in danger too. We do some splicing outdoors with home drop cables. Most of the ...
user91107's user avatar

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